88 lines
2.2 KiB
Markdown
88 lines
2.2 KiB
Markdown
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go-shp
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======
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[](https://travis-ci.org/jonas-p/go-shp)
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[](https://ci.appveyor.com/project/fawick/go-shp)
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[](https://goreportcard.com/report/github.com/jonas-p/go-shp)
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[](https://codecov.io/gh/jonas-p/go-shp)
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Go library for reading and writing ESRI Shapefiles. This is a pure Golang implementation based on the ESRI Shapefile technical description.
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### Usage
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#### Installation
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go get github.com/jonas-p/go-shp
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#### Importing
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```go
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import "github.com/jonas-p/go-shp"
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```
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### Examples
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#### Reading a shapefile
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```go
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// open a shapefile for reading
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shape, err := shp.Open("points.shp")
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if err != nil { log.Fatal(err) }
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defer shape.Close()
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// fields from the attribute table (DBF)
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fields := shape.Fields()
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// loop through all features in the shapefile
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for shape.Next() {
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n, p := shape.Shape()
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// print feature
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fmt.Println(reflect.TypeOf(p).Elem(), p.BBox())
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// print attributes
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for k, f := range fields {
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val := shape.ReadAttribute(n, k)
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fmt.Printf("\t%v: %v\n", f, val)
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}
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fmt.Println()
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}
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```
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#### Creating a shapefile
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```go
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// points to write
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points := []shp.Point{
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shp.Point{10.0, 10.0},
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shp.Point{10.0, 15.0},
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shp.Point{15.0, 15.0},
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shp.Point{15.0, 10.0},
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}
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// fields to write
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fields := []shp.Field{
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// String attribute field with length 25
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shp.StringField("NAME", 25),
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}
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// create and open a shapefile for writing points
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shape, err := shp.Create("points.shp", shp.POINT)
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if err != nil { log.Fatal(err) }
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defer shape.Close()
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// setup fields for attributes
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shape.SetFields(fields)
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// write points and attributes
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for n, point := range points {
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shape.Write(&point)
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// write attribute for object n for field 0 (NAME)
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shape.WriteAttribute(n, 0, "Point " + strconv.Itoa(n + 1))
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}
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```
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### Resources
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- [Documentation on godoc.org](http://godoc.org/github.com/jonas-p/go-shp)
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- [ESRI Shapefile Technical Description](http://www.esri.com/library/whitepapers/pdfs/shapefile.pdf)
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